Which of the following is a non-reactive gas that can be used for diffused air ventilation?

Nitrogen is a non-reactive gas, which means it does not readily engage in chemical reactions under standard conditions. This characteristic makes nitrogen particularly suitable for diffused air ventilation systems, as it can be used to purge or replace other gases without risking unwanted chemical reactions or alterations in air quality.

In diffused air ventilation, maintaining a neutral and stable environment is crucial, especially in settings like storage tanks or enclosed spaces where the presence of reactive gases could lead to hazardous situations or contamination. Nitrogen's inert nature ensures that it is safe to use in these applications.

Oxygen, on the other hand, is highly reactive and supportive of combustion, making it unsuitable where an inert atmosphere is needed. Hydrogen is also reactive and poses safety risks related to flammability. Argon, while inert like nitrogen, is denser and less prevalent in the atmosphere, which makes it less practical for large-scale ventilation as compared to nitrogen, which is abundant and cost-effective.